# RaspberryPi-bmp180 not providing output

**URL:** <https://discourse.nodered.org/t/raspberrypi-bmp180-not-providing-output/8251>\
**Category:** General\
**Created:** [22 February 2019 00:33 UTC](https://discourse.nodered.org/t/raspberrypi-bmp180-not-providing-output/8251 "2019-02-22T00:33:31Z")\
**Posts on this page:** 7\
**Page:** 1

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**Author:** ![chuckf201](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/chuckf201/32/91382_2.png) [@chuckf201](https://discourse.nodered.org/u/chuckf201)\
**Post date:** [22 February 2019 00:33 UTC](https://discourse.nodered.org/t/raspberrypi-bmp180-not-providing-output/8251/1 "2019-02-22T00:33:31Z")

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I'm using node-red-contrib-brads-i2c-nodes to read temperature and pressure. I also have a python script that works successfully but wanted to try my hand at Node-Red.  
I'm new to Node-Red but am frustrated.  
Error is: 2/21/2019, 7:26:43 PM[node: 1cd94fa8.b7ae4](http://192.168.50.XXX:1880/#)  
msg.payload : string[22] " unrecognized command."  
node bmp180 "ready"  
node bmp180 output: msg.payload.temperature  
I don't know what to send to node bmp180 to read it from the inject node.  
It seem that the upstream node are not configured correctly.  
Any help would be appreciated.

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**Author:** ![ukmoose](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/ukmoose/32/13_2.png) [@ukmoose](https://discourse.nodered.org/u/ukmoose)\
**Post date:** [22 February 2019 09:26 UTC](https://discourse.nodered.org/t/raspberrypi-bmp180-not-providing-output/8251/2 "2019-02-22T09:26:27Z")

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If you click on the `1cd94fa8.b7ae4` bit in the debug it should highlight the node that is causing the error.

How have you configured the bmp180 node you are using?

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**Author:** ![chuckf201](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/chuckf201/32/91382_2.png) [@chuckf201](https://discourse.nodered.org/u/chuckf201)\
**Post date:** [22 February 2019 14:25 UTC](https://discourse.nodered.org/t/raspberrypi-bmp180-not-providing-output/8251/3 "2019-02-22T14:25:58Z")

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bmp180: node imput: none  
node output: 1. msg.payload.temperature  
node output: 2 msg.payload.humidity  
topic: temperature  
node says "ready"  
node function:  
msg.payload = msg.payload;  
return msg;  
node debug:  
input: msg.payload  
output: msg.payload  
i'm kicking off the project by injecting time (hoping is is not used).  
1550845445544 unrecognized command. \<--- timestamp?  
node-red messages:  
21 Feb 19:41:52 - [info] [bmp180:bmp180] {"id":"3d9c10af.110338","type":"bmp180","z":"f6294210.397ab8","name":"bmp180","topic":"temperature","presolution":244,"debugMode":true,"x":320,"y":220,"wires":[["ad5994d2.58464","1cd94fa8.b7ae4"],[]],"outputLabels":["msg.payload.temperature","msg.payload.humidity"]}  
21 Feb 19:41:52 - [info] [bmp180:BMP180 @ 0x77] node.p\_oversampling -\> {"timeMs":26,"value":244,"oss":3,"samples":8}  
21 Feb 19:41:52 - [info] Started flows  
21 Feb 19:41:52 - [info] [bmp180:BMP180 @ 0x77]  
bmp180 calibration parameters loaded.  
Calibration Address: 0x8889 AC1 -\> 0x1e6b (7787)  
Calibration Address: 0x8a8b AC2 -\> 0x-4ac (-1196)  
Calibration Address: 0x8c8d AC3 -\> 0x-3990 (-14736)  
Calibration Address: 0x8e8f AC4 -\> 0x830e (33550)  
Calibration Address: 0x9091 AC5 -\> 0x5e69 (24169)  
Calibration Address: 0x9293 AC6 -\> 0x4359 (17241)  
Calibration Address: 0x9495 B1 -\> 0x157a (5498)  
Calibration Address: 0x9697 B2 -\> 0x40 (64)  
Calibration Address: 0x9899 MB -\> 0x-8000 (-32768)  
Calibration Address: 0x9a9b MC -\> 0x-2b43 (-11075)  
Calibration Address: 0x9c9d MD -\> 0x980 (2432)  
21 Feb 19:41:52 - [info] [bmp180:BMP180 @ 0x77] BMP180 @ 0x77 ready.  
21 Feb 19:41:52 - [info] [bmp180:BMP180 @ 0x77] {"topic":"","payload":"1550796112167 unrecognized command.","\_msgid":"5365c8bf.9b0268"}  
21 Feb 19:41:52 - [info] [debug:1cd94fa8.b7ae4] 1550796112167 unrecognized command.  
21 Feb 19:41:52 - [info] [debug:1cd94fa8.b7ae4] 1550796112167 unrecognized command.  
node 1cd941a8.b7ae4 is a debug node

Hope this help.

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<div class="post-metadata">

**Author:** ![dceejay](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/dceejay/32/38_2.png) [@dceejay](https://discourse.nodered.org/u/dceejay)\
**Post date:** [22 February 2019 17:18 UTC](https://discourse.nodered.org/t/raspberrypi-bmp180-not-providing-output/8251/4 "2019-02-22T17:18:08Z")

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Looking at the code for that node it seems you need to send it a string "measure" for it to reply correctly - change your inject to send that and see what happens.

From the overall project readme

```auto
All nodes use an [inject] node to send a string command of 'measure' to initiate sensor measurement based on values set in the config panels of the flow diagram.

```

But yeah - docs is not his thing... maybe worth raising an issue on the github page for that node to add something to the info for each node - but it's been a while since he touched it.

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**Author:** ![chuckf201](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/chuckf201/32/91382_2.png) [@chuckf201](https://discourse.nodered.org/u/chuckf201)\
**Post date:** [22 February 2019 21:51 UTC](https://discourse.nodered.org/t/raspberrypi-bmp180-not-providing-output/8251/5 "2019-02-22T21:51:31Z")

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dceejay - You're right on. Where is this documented?  
2/22/2019, 4:48:39 PM[node: 1cd94fa8.b7ae4](http://192.168.50.132:1880/#)bmp180 : msg.payload : Object

object

name: "BMP180 @ 0x77"

timestamp: "2/22/2019, 16:48:38"

Tc: "30.90"

Tf: "87.61"

p: "101814.90"

P: "30.07"

altm: "-40.71"

altf: "-12.41"

Thanks for your help

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<div class="post-metadata">

**Author:** ![dceejay](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/dceejay/32/38_2.png) [@dceejay](https://discourse.nodered.org/u/dceejay)\
**Post date:** [22 February 2019 22:12 UTC](https://discourse.nodered.org/t/raspberrypi-bmp180-not-providing-output/8251/6 "2019-02-22T22:12:51Z")

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It's on the main project page for the node you mentioned

> **[pedalPusher68/node-red-contrib-brads-i2c-nodes](https://github.com/pedalPusher68/node-red-contrib-brads-i2c-nodes)**
>
> A collection of node-red nodes for assorted i2c devices - pedalPusher68/node-red-contrib-brads-i2c-nodes

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<div class="post-metadata">

**Author:** ![chuckf201](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/chuckf201/32/91382_2.png) [@chuckf201](https://discourse.nodered.org/u/chuckf201)\
**Post date:** [22 February 2019 23:13 UTC](https://discourse.nodered.org/t/raspberrypi-bmp180-not-providing-output/8251/7 "2019-02-22T23:13:16Z")

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Ah, yes. I see it now.  
Thank you again.  
I have soo much to learn.  
Chuck